Snowfall warning posted for Montreal

The clean up continues from the last two storms to impact the Montreal region. Another major storm system, the third this week, is on the way for Friday night and Saturday, with 10 to 25cm of snow forecast across a wide region from southern Ontario into Quebec. Very strong winds will produce near-blizzard conditions at times. (Valley Weather Photo)

Snowfall warning in effect for metro Montreal for 15-20cm of snow and blowing snow Friday night.

Expect very difficult travel conditions tonight and Saturday.

Widespread weather warnings are in effect across Quebec and Ontario as we await the arrival of our third winter storm in less than a week. This storm will be very similar to Tuesday nights system, following a similar track and just as strong. 

We can expect an initial surge of moisture around midnight Friday, that will deposit a quick 10cm of snow across the region. The snow will be accompanied by gusty northeast winds, up to 50km/h in the St. Lawrence Valley. Winter storm warnings have been issued across much of eastern Ontario and regions north of Montreal, where up to 30cm of snow is possible.

Heavy snow is forecast for Quebec City, with up to 20cm along with northeast winds up to 80km/h and near blizzard conditions at times.

Across the Eastern Townships, milder air will result in less snow and more rainfall, as temperatures rise to 5C (41F) Saturday. Strong winds of up to 80km/h are possible across the same region that experienced widespread power outages on Wednesday.

Low pressure is rapidly deepening across the Midwest US early Friday morning, forecast to lift into the eastern Great Lakes today and across southern Quebec on Saturday. Along and south of the St. Lawrence River, warmer air may allow for a brief mix of precipitation on Saturday. Winds will remain strong Saturday, eventually backing to the southwest and west, gusting in excess of 70km/h late Saturday.

In terms of temperatures, Friday will be chilly, with a high near -7C (19F). Overnight temperatures will be on the rise to 1C (33F) by midday Saturday. Colder air will filter in behind the storm late Saturday, down to -4C (26F) and remaining steady Sunday.

Windy weather is expected Sunday, along with frequent snow flurries, as strong southwest winds push lake effect snow down the St. Lawrence Valley from Lake Ontario.

Colder air will surge into the central portion of the continent next week, with near to below normal temperatures forecast through the end of the month for the Montreal region.